Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations only declare readOnlyHint, so the description carries most of the burden and does add real traits: it returns only added/changed sections (unchanged content is omitted), produces deletion tombstones, and honors a conservative token budget with continuation behavior. It doesn't mention auth or failure/expiry semantics for the cursors, keeping it below a 5.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two tight, front-loaded sentences with no filler; the scoping behavior is stated first. Slightly dense phrasing ('digest-bound continuation cursors') compresses some explanation that is never expanded.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists so return values need not be detailed, and readOnlyHint covers the safety profile. The description adequately ties the tool to its prerequisite and its incremental/diff nature, though the required 'since' parameter's expected value remains unspecified.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is only 25%, so the description should compensate more. It does explain cursor (continuation) and tokenBudget (conservative budget) in behavior terms, but leaves 'since' and 'locale' entirely unexplained — 'since' is the required parameter and gets no format or provenance hints.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

Specific verb (fetch/hydrate) plus a precise resource (added and changed agent-facing sections) and explicit sequencing with the sibling list_content_changes. An agent can distinguish it from list_content_changes and read_page without opening schemas.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The phrase 'after list_content_changes' clearly establishes the prerequisite call and ordering, which is valuable usage guidance. It does not state when NOT to use it or name other alternatives (e.g., read_page for full content), so it falls short of the explicit-exclusions bar.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.